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This cohort study assesses whether postoperative complications are associated with having been diagnosed with a mental health condition in patients who have undergone gender-affirming surgery.

Objective To review the evidence suggesting a significant association between gout and erectile dysfunction (ED) and evaluate possible underlying pathways that may explain this relationship. Methods English medical literature was searched from January 1, 2010, to January 1, 2020, for randomized or quasi-randomized controlled trials, cross-sectional studies, case-cohort studies, or meta-analysis evaluating the relationship between gout and ED. Results All nine gout studies included in the study found a significant association between gout and ED. ED pathophysiology in gout involves hyperuricemia, increased reactive oxygen species, decreased nitric oxide synthesis, and low-grade inflammation. Conclusion The findings of this review suggest that the effect of urate-lowering therapy on the incidence of ED in gout patients should be studied. Additionally, we propose that all gout patients should be assessed for ED.

To determine preference-based (utility) assessments of health-related quality of life (HRQoL) in kidney stone patients, and evaluate the association between these and disease specific, psychometric health status-based HRQoL scores (obtained via the Wisconsin Stone Quality of Life [WISQOL]).One hundred four adults with urolithiasis, as well as 78 young healthy adults without history of urolithiasis (controls) were consecutively enrolled, meeting the predetermined recruitment goal. Each participant completed the SF-36 v2 (from which SF-6D utility is calculated) and EQ-5D questionnaires, while urolithiasis patients additionally completed the WISQOL. Relationship between health utility and WISQOL scores was evaluated using Pearson's test and multivariable linear regression analysis (MVA). Construct validity of the utilities for urolithiasis was assessed by comparing utilities for patients vs controls, and for symptomatic vs asymptomatic patients.Mean (SD) WISQOL standard score, SF-6D, and EQ-5D utilities in stone patients respectively were 63 (29.1), 0.68 (0.16), and 0.83 (0.17). SF-6D and EQ-5D utilities significantly correlated with WISQOL standard score (Pearson's r = 0.87 and 0.58, respectively; each P.0001). On MVA, WISQOL standard score was a significant predictor of SF-6D and EQ-5D utilities, explaining 72.1% and 33.9% of the respective variances in the utilities. Median SF-6D and EQ-5D utility were significantly lower in patients vs controls (each P ≤.0009), and in symptomatic vs asymptomatic patients (each P ≤ .0002).SF-6D, more so than EQ-5D utilities in urolithiasis patients are strongly associated with disease-specific WISQOL scores, suggesting they are optimal for preference-based HRQoL assessment in this population. Construct validity of the utilities in stone disease was demonstrated.

Background The United States healthcare landscape has witnessed numerous changes since implementation of the Affordable Care Act coupled with rising prevalence of upper urinary tract stone disease. Data on the economic burden of stone disease during this period are lacking, providing the objective of our study. Materials and Methods Adults diagnosed with stone disease from 2011-2018 were identified from PearlDiver Mariner, a national all-payer database reporting reimbursements and prescription costs for all healthcare encounters. Patients undergoing operative and non-operative care were identified. Time trends in annual expenditures were evaluated. Multivariable analysis evaluated determinants of spending. Results A total of $10B were spent on stone disease management between 2011-2018 (median overall annual expenditure=$1.4B) among 786,756 patients. Inpatient, prescription and outpatient costs accounted for 34.7%, 20.7% and 44.6% of expenditures respectively. 78% of patients were managed non-operatively (total cost=$6.9B). Average overall cost per encounter was $13,587 ($17,102 for surgical vs. $11,174 for non-surgical care). Expenditures on inpatient care decreased significantly over time, while expenditures on prescriptions and outpatient care increased significantly. On multivariable analysis, higher Charlson Comorbidity Index was associated with higher spending, while associations for age, insurance and region varied by treatment modality. Conclusions The economic burden of stone disease management is substantial, dominated by expenditure on non-operative management and outpatient care. Expenditures for prescription and outpatient care are rising, with the only consistent predictor of higher spending being Charlson Comorbidity Index. Spending variation according to demographic, clinical, and geographic factors was evident.

INTRODUCTION AND OBJECTIVE:A majority of stented patients experience negatively impacted HRQoL, modifiable by stent biomaterial, length and/or pharmacologic treatment. However, the optimal combinat...

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Introduction: Calculous nephrectomy was a mainstay of treatment of complex upper tract stone disease up until the 1970s, but data on its contemporary utilization in the current era of risi...

Phyllanthus niruri (P. niruri) is the most commonly listed active ingredient in commercially available herbal therapies for kidney stones, despite limited supporting clinical evidence. We performed a meta-analysis to evaluate its efficacy in reducing stone burden. We used Google Trends to analyze its relative popularity in internet searches relative to conventional stone therapies.A comprehensive literature search for controlled human studies containing data on the effect of P. niruri treatment on stone size and number was performed. Pooled analysis of change in mean stone size and number with P. niruri was performed using a fixed-effects model. Standardized mean difference (SMD) and 95% CI were reported. Google searches in the United States within the 'Health' category, for topics 'Gale of the wind (P. niruri)', 'Extracorporeal shockwave lithotripsy' (ESWL), 'Ureteroscopy' (URS), 'Laser lithotripsy' (URSL) and 'Percutaneous nephrolithotomy' (PCNL), conducted between January 2014 and December 2018, were quantified. Annual median relative search volumes (RSV; 0-100 scale) were compared using the Kruskal-Wallis test. Post-hoc pairwise comparisons were performed using the Dunn test with Holm-Sidak adjustment.Two studies met inclusion criteria. P. niruri treatment resulted in significant decreases in mean stone size (SMD -0.39 cm, 95% CI = -0.68 to -0.09, p = 0.01) and number (SMD -0.38, 95% CI = -0.68 to -0.09, p = 0.01). Median RSV for P. niruri was similar to that for ESWL, PCNL and URS through 2015, but was significantly higher than for ESWL and PCNL after 2015, and higher than for URS after 2016 (each p value p ≤ 0.0012).Limited clinical evidence supports modest efficacy of P. niruri in reducing stone burden, pending further study. Public interest in P. niruri is growing within the United States, possibly reflecting a rising demand.

INTRODUCTION AND OBJECTIVE:People have eaten genitourinary offal, or non-muscle meat, since biblical times. We present a brief history of the use of kidneys and testes as food in both ancient and c...

We performed a network meta-analysis of available randomized, controlled trials to elucidate the risks of urinary tract infection associated with transurethral catheterization, suprapubic tubes and intermittent catheterization in the postoperative setting.PubMed®, EMBASE® and Google Scholar™ searches were performed for eligible randomized, controlled trials from January 1980 to July 2015 that included patients who underwent transurethral catheterization, suprapubic tube placement or intermittent catheterization at the time of surgery and catheterization lasting up to postoperative day 30. The primary outcome of comparison was the urinary tract infection rate via a network meta-analysis with random effects model using the netmeta package in R 3.2 (www.r-project.org/).Included in analysis were 14 randomized, controlled trials in a total of 1,391 patients. Intermittent catheterization and suprapubic tubes showed no evidence of decreased urinary tract infection rates compared to transurethral catheterization. Suprapubic tubes and intermittent catheterization had comparable urinary tract infection rates (OR 0.903, 95% CI 0.479-2.555). On subgroup analysis of 10 randomized, controlled trials with available mean catheterization duration data in a total of 928 patients intermittent catheterization and suprapubic tube were associated with significantly decreased risk of urinary tract infection compared to transurethral catheterization when catheterization duration was greater than 5 days (OR 0.173, 95% CI 0.073-0.412 and OR 0.142, 95% CI 0.073-0.276, respectively).Transurethral catheterization is not associated with an increased urinary tract infection risk compared to suprapubic tubes and intermittent catheterization if catheterization duration is 5 days or less. However, a suprapubic tube or intermittent catheterization is associated with a lower rate of urinary tract infection if longer term catheterization is expected in the postoperative period.

The lens of the eye is extremely susceptible to radiation and long-term exposure can induce cataract formation. Our objective was to explore the risk of cataract formation for urologists at our institution.A retrospective review of a multisurgeon database of fluoroscopic cases between October 2013 to December 2014 was queried. Procedures were performed by different subspecialties and ranged from stent insertion/ureteroscopy to percutaneous nephrolithotomy. Fluoroscopic parameters were recorded from all cases and the radiation dosimetry was calculated through methods described by the National Council on Radiation Protection. The data were extrapolated to determine the risk of cataract formation. The technical specifications of the GE OEC 990 mobile C-arm unit were used for calculations.A total of 780 cases were analyzed, of which 182 were endourology cases. Average fluoroscopic time was 34.86 seconds per case. Average tube potential and current were 86.84 kV and 1.95 mA, respectively. Pediatric urologists utilized fluoroscopy the least, 11.84 seconds per case (p = 0.0022). Endourology trained faculty had fluoroscopy exposure of 68.35 seconds per case (p 0.0001), whereas others were exposed 26.24 seconds per case (p 0.0001). For the highest exposed urologist, the estimated dose to the eyes was 5.64 μGy per case. Total estimated cumulative dose over the study timeframe was 997.58 μGy, or 748.19 μGy per year.The defined threshold in the absorbed dose for cataract formation is 0.5 Gy. Resident exposure was the highest, at 11% of the annual limit, and the most exposed urologists had an estimated dose of 5% of the annual limit. At current exposure levels, it would not be feasible to reach the stated safety limit during 50 to 60 years of practice. However, changing exposure guidelines could result in stricter safety limits.

To describe population-wide utilization rates and outcomes of percutaneous nephrolithotomy (PCNL) in the management of pediatric upper urinary tract calculi (UUTC).Patients18 years with a diagnosis of UUTC, who underwent PCNL between 2001 and 2014 were identified from the National Inpatient Sample database. Annual PCNL rates, based on the at-risk population for each year, were estimated, and change in utilization rate was analyzed using negative binomial regression. Perioperative outcomes, hospital length of stay (LOS), and costs were determined; continuous and categorical variables were analyzed using nonparametric tests and Chi-squared tests, respectively. Trends tests and multivariable analyses (MVAs) were also performed where appropriate.An estimated 3206 pediatric PCNL procedures were performed. Mean annual PCNL rate increased significantly relative to 2001 (incidence rate ratio = 1.40; 95% confidence interval 1.15-1.71, p = 0.001). Proportion of PCNL as a fraction of all inpatient surgical procedures for UUTC also significantly increased over time, from 15.7% in 2001 to 26.4% in 2014 (p 0.0001). Complications overall occurred in 20.7% of cases, with a significantly rising rate over time period (p 0.0001). Complication rates were similar across hospital types and geographic regions. Median hospitalization cost was significantly higher for the West than for each of the other regions (p 0.05 in each case). Median LOS was also highest for the West (4 days vs 3 days for each of the other regions). In MVA, significant predictors of both increased LOS and costs included black race, comorbidities of hypertension, diabetes, coagulopathy and neurologic disease, hospitalization in the South, and presence of complications. Race, gender, comorbidities, and treatment year were among the predictors of complications.PCNL utilization in the management of pediatric UUTC has significantly increased since 2001, with an associated increase in complication rates, although major complications were uncommon. Regional variations in costs and LOS were evident.

Current radio frequency ablation series do not distinguish renal cell carcinoma subtypes when reporting oncologic efficacy. Papillary neoplasms may be more amenable to radio frequency ablation than clear cell carcinoma because they are less vascular, which may limit heat energy loss. We report the long-term outcomes of patients treated with radio frequency ablation for small renal masses by renal cell carcinoma subtype.The records of patients undergoing radio frequency ablation for small renal masses (cT1a) at 2 institutions from March 2007 to July 2012 were retrospectively reviewed. Patients were included in analysis if they had biopsy confirmed clear cell or papillary renal cell carcinoma histology. Patients had at least 1 contrast enhanced cross-sectional image following radio frequency ablation. Demographic data between tumor subtypes were compared using the paired t-test. Oncologic outcomes were determined by Kaplan-Meier survival analysis and survivor curves were compared with the log rank test.A total of 229 patients met study inclusion criteria. There were 181 clear cell tumors and 48 papillary tumors. Median followup was 33.2 months. There was no difference between tumor groups based on patient age, tumor size or grade, or months of followup. Five-year disease-free survival was 89.7% for clear cell tumors and 100% for papillary tumors (p = 0.041). There was no significant difference in overall survival (88.4% vs 89.6%, p = 0.764).Radio frequency ablation outcomes seem to be determined in part by renal cell carcinoma subtype with clear cell renal tumors having less favorable outcomes. We hypothesize that this is due to differences in tumor vascularity. Our experience suggests that future tumor ablation studies should consider reporting outcomes based on tumor cell types.

Objective To assess the predictive performance of a modified RENAL nephrometry score for renal tumors undergoing radiofrequency ablation (RFA). Methods Patients who underwent RFA were identified from 2002 to 2011, and RENAL nephrometry scoring was performed for each. A modified RENAL (m-RENAL) nephrometry score was created to account for the small sizes of tumors ablated for which the size variable, R, was adjusted. A size of 3 cm was calculated as the optimal cutoff for the R component of the m-RENAL nephrometry score, and tumors were given an R score of 1 if 4 cm. Other RENAL variables were unchanged. Oncologic outcomes were stratified by complexity tertiles defined as low (4-6), medium (7-9), and high (10-12). Outcomes were reported as initial ablation success (IAS), recurrence-free survival (RFS), and metastatic-free survival (MFS). The Kaplan-Meir method was used to estimate survival based on complexity tertile. Results Two hundred forty patients were identified who underwent RFA, of which 192 patients were eligible for analysis. Median follow-up was 32.2 months, and median tumor size was 2.4 cm. IAS was achieved in 185 of 192 patients (96.4%). Overall, the estimated 3-year RFS was 95.1% and MFS was 97.3%. There was no statistical difference between complexity tertiles using the standard RENAL nephrometry score; however, the m-RENAL nephrometry score was significantly associated with IAS and RFS ( P = .027 and P = .003, respectively). There were too few events (n = 3) to perform statistical analysis for MFS. Conclusion A modification to the size variable increases the performance of the RENAL nephrometry score when used to stratify RFA ablation success.

Nearly two-thirds of newly detected renal masses are clinical stage 1, with T1a tumours accounting for 60% of the newly detected stage 1 tumours. Guideline panels convened by the American Urological Association and the European Association of Urology recommend nephron-sparing surgery as the gold standard treatment for small renal masses, with active surveillance and thermal ablation recommended as alternative strategies in select patients. However, there is a dearth of studies directly comparing outcomes for energy-based ablation to those for traditional surgical treatments for small renal masses, and future prospective randomized trials will be invaluable in this regard. Ongoing research in renal tumour ablation targets several areas, including but not limited to achieving larger ablation sizes, decreasing morbidity, and development of novel technologies for renal tumour ablation.

The incidence of urolithiasis in the pediatric population in the United States has steadily been increasing over the past few decades. Few studies to date have examined trends in the hospitalization and inpatient surgical treatment of urolithiasis in the pediatric population using nationally representative data.The aim was to evaluate nationwide trends in the rates of pediatric hospitalization and inpatient surgical activity for upper urinary tract calculi (UUTC) in the United States from 2001 to 2014.The National Inpatient Sample (NIS) databases for 2001-2014 were queried. Hospitalizations for patients younger than age 18 (excluding newborns), with principal discharge diagnoses of kidney or ureteral calculi were selected. Surgical procedures during hospitalization were identified. Hospitalization and surgical activity data were analyzed using trends tests, chi-square statistics, and multivariable logistic regression as appropriate.Of an estimated 30.2 million pediatric hospitalizations during the study period, 44,369 overall (147 per 100,000) were for UUTC. The total number and proportion of UUTC hospitalizations per 100,000 all-cause admissions significantly decreased between 2001 and 2014 (p 0.0001) (figure). Surgical intervention was undertaken in 19,946 (45%) of UUTC hospitalizations, with significantly increasing frequency over the study interval (p 0.0001). Urinary tract drainage was the most frequently performed surgical intervention. On multivariable analysis, significant predictors of a higher likelihood of undergoing inpatient surgical intervention during hospitalization for UUTC included older age, female gender, deficiency anemias, hypertension, neurologic disorders, paralysis, and hospitalization after 2001.The declining trend in hospitalization for UUTC likely reflects a shift toward outpatient care for routine cases, reserving hospitalization for sicker patients or those with complications of urolithiasis. Similar to previous studies, we also observed that girls were significantly more likely than boys to be hospitalized for stone disease, and that majority of the stone activity in the pediatric population was in children aged 15-17 years. We also observed a sharp increase in the proportion of hospitalized patients who underwent surgical intervention between 2001 and 2014, but the primary driver of this trend remains uncertain.Pediatric hospitalizations for UUTC in US children significantly decreased between 2001 and 2014, while of those hospitalized the proportion who underwent stone-related surgical intervention significantly increased over the same period. A shift towards outpatient care, reserving hospitalization and inpatient surgical care for sicker patients, those with urolithiasis-related complications, or those who fail conservative management, is a possible explanation for these observed trends.

Objectives To assess whether the R.E.N.A.L. nephrometry score (consists of [R]adius [tumour size as maximal diameter], [E]xophytic/endophytic properties of the tumour, [N]earness of tumour deepest portion to the collecting system or sinus, [A]nterior [a]/posterior [p] descriptor and the [L]ocation relative to the polar line) is associated with complication risk in patients that have radiofrequency ablation (RFA) for small renal masses (SRMs). To evaluate a standardised system for predicting complication risks which has not been studied. Patients and Methods We reviewed the records of all patients who underwent RFA at our institution between May 2001 and May 2011. RFA was performed using a temperature-based system and a 25-G nine-tine array needle probe. Patients with preoperative imaging available for R.E.N.A.L. nephrometry scoring were included. R.E.N.A.L. composite scores, tertile stratification and preoperative patient characteristics were analysed for significance in relation to complications. Complications were defined using the Clavien-Dindo classification system. Results In all, 199 patients had preoperative R.E.N.A.L. nephrometry scores available; 170 underwent percutaneous RFA and 29 laparoscopic RFA. The mean (range) American Society of Anesthesiologists (ASA) score was 2.6 (1–4). The mean (range) tumour size was 2.4 (0.7–5.4) cm. Overall, 14 complications were identified; 10 minor (Clavien I–II) and four major (Clavien III–IV). There was no significant association between complications and R.E.N.A.L. nephrometry score, R.E.N.A.L. nephrometry tertiles, tumour diameter, tumour location or ASA score (P > 0.05). Conclusion R.E.N.A.L. nephrometry scoring fails to predict complications of RFA for SRMs when using a temperature-based nine-tine array probe.

Digital Light Processing hyperspectral imaging (HsI) produces a highly sensitive, real-time tissue oxygenation map to monitor renal perfusion/oxygenation during partial nephrectomy (PN). Our initial experience with HsI revealed considerable variation in the baseline renal oxygenation, and we sought to correlate these differences with postoperative renal function.Hyperspectral images were collected intraoperatively in patients undergoing PN for cortical tumors. The kidney was illuminated with visible light (520-645 nm), the spectrum corresponding to that of oxyhemoglobin. Reflectance images were captured and digitally processed to determine the percentage of oxyhemoglobin (HbO2) at each image pixel. Images were taken before hilar occlusion; these %HbO2 values were used to categorize patients as high (75% HbO2) or low (75% HbO2) oxygenation, and postoperative eGFR was assessed.There were 26 patients who underwent PN with ice cooling and HsI imaging. Nineteen patients had a "low" preclamp oxygenation (mean 69%) while the other 7 had a "high" HbO2 (mean 77%). There was no difference in tumor size, hematocrit value, clamp time, or preoperative eGFR between the two groups. Patients with a higher baseline %HbO2 had no significant postoperative change in their eGFR (mean 0 mL/min/1.73 m(2), +4%), while those with the lower baseline %HbO2 had a significant acute decline (mean 15 mL/min/1.73 m(2), -20%, P=0.02, 0.006).Baseline renal oxygenation, as measured with HsI, may help predict risk of postoperative renal insufficiency and may distinguish between patients with otherwise similar baseline characteristics, such as eGFR. HsI may provide individualized assessment of renal function to influence intraoperative decision-making to help preserve renal function.

During partial nephrectomy (PN), artery-only (AO) occlusion may mitigate ischemia/reperfusion injury because of retrograde venous flow. Using digital light processing-hyperspectral imaging (DLP(®)-HSI), we compared renal oxygenation during AO vs artery and vein (AV) occlusion in patients undergoing PN.Thirty-seven patients who were undergoing complex open PN (median R.E.N.A.L. nephrometry of 8) at our institution underwent renal oxygenation assessment using DLP-HSI. Percent renal parenchymal oxyhemoglobin (%HbO2) during AO vs AV occlusion was recorded and its correlation with postoperative estimated glomerular filtration rate (eGFR) was investigated using Pearson correlation. AO and AV occlusion was performed in 12 and 25 patients, respectively.Comparing AO vs AV, mean ischemia time was 41 vs 35 minutes (P=0.02). The %HbO2 at baseline was 73.6% vs 71% (P=0.23). After hilar occlusion, %HbO2 quickly reached an "ischemic plateau" in both groups, with mean ischemic %HbO2 measures of 59.7% vs 62.2% (P=0.19). In the AV group, a lower mean ischemic %HbO2 was associated with lower eGFR at the most recent follow-up (r=0.46, P=0.02) and remained significant on multivariable analysis (odds ratio 2.31; 95% confidence interval 0.29-4.32; P=0.03).In this pilot clinical study, renal oxygenation profiles during PN as assessed by DLP-HSI were similar for AO vs AV occlusion. Significant retrograde venous oxygen delivery using an AO occlusion technique could not be demonstrated. There was also no renal functional advantage for AO occlusion in this population of difficult PN where prolonged ischemia times may have mitigated any advantage. Further study in cases with shorter ischemia times is warranted.

To compare surgeon-assessed ergonomic and workload demands of magnetic anchoring and guidance system (MAGS) laparoendoscopic single-site surgery (LESS) nephrectomy with conventional LESS nephrectomy in a porcine model.Participants included two expert and five novice surgeons who each performed bilateral LESS nephrectomy in two nonsurvival animals using either the MAGS camera or conventional laparoscope. Task difficulty and workload demands of the surgeon and camera driver were assessed using the validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire. Surgeons were also asked to score 6 parameters on a Likert scale (range 1=low/easy to 5=high/hard): procedure-associated workload, ergonomics, technical challenge, visualization, accidental events, and instrument handling. Each step of the nephrectomy was also timed and instrument clashing was quantified.Scores for each parameter on the Likert scale were significantly lower for MAGS-LESS nephrectomy. Mean number of internal and external clashes were significantly lower for the MAGS camera (p0.001). Mean task times for each procedure were shorter for experts than for novices, but this was not statistically significant. NASA-TLX workload ratings by the surgeon and camera driver showed that MAGS resulted in a significantly lower workload than the conventional laparoscope during LESS nephrectomy (p0.05).The use of the MAGS camera during LESS nephrectomy lowers the task workload for both the surgeon and camera driver when compared to conventional laparoscope use. Subjectively, it appears to also improve surgeons' impressions of ergonomics and technical challenge. Pending approval for clinical use, further evaluation in the clinical setting is warranted.

Objective To compare the renal ablative capabilities of nonthermal irreversible electroporation (NT-IRE) with those of thermal irreversible electroporation (T-IRE) in a porcine model. Materials and Methods A total of 24 laparoscopic renal ablations were performed in 12 pigs using a novel generator capable of alternately delivering NT-IRE and T-IRE. Each pig underwent unilateral interpolar ablation straddling the renal pelvis and lower pole ablation, using a single modality. The pigs were killed at 24 hours and 7 and 21 days. Basic serum laboratory tests, cardiac enzyme levels, and retrograde pyelograms were obtained before and immediately after ablation and at death. Ablation adequacy and lesion size were assessed by histologic examination. Results All procedures were successfully completed without complications. For NT-IRE vs T-IRE, the median lesion size (long axis) at 24 hours, 7 days and 21 days was 3.0 vs 3.3 cm ( P = 1.0), 2.5 vs 3.9 cm ( P = .04), and 1.2 vs 2.8 cm ( P = .03), respectively. Prolonged urinary extravasation and collecting system scarring were observed only for T-IRE. Both NT-IRE and T-IRE ablated the renal tissue adequately. NT-IRE was characterized by acute hemorrhagic necrosis, sparing the large blood vessels and extracellular matrix, and T-IRE by coagulation necrosis with associated moderate inflammation. Conclusion NT-IRE and T-IRE both safe and effectively ablate normal porcine kidneys. NT-IRE created smaller lesions with unique histologic characteristics. Significant collecting system injury occurred with T-IRE. Additional preclinical evaluation aimed at optimizing the ablation protocols is needed.

To compare the ergonomics and workload of the surgeon during single-site suturing while using the magnetic anchoring and guidance system (MAGS) camera vs a conventional laparoscope.Seven urologic surgeons were enrolled and divided into an expert group (n=2) and a novice group (n=5) according to their laparoendoscopic single-site (LESS) experience. Each surgeon performed 2 conventional LESS and 2 MAGS camera-assisted LESS vesicostomy closures in a porcine model. A Likert scale (scoring 1-5) questionnaire assessing workload, ergonomics, technical difficulty, visualization, and needle handling, as well as a validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire were used to evaluate the tasks and workloads.MAGS LESS suturing was universally favored by expert and novice surgeons compared with conventional LESS in workload (3.4 vs 4.2), ergonomics (3.4 vs 4.4), technical challenge (3.3 vs 4.3), visualization (2.4 vs 3.3), and needle handling (3.1 vs 3.9 respectively; P.05 for all categories). Surgeon NASA-TLX assessments found MAGS LESS suturing significantly decreased the workload in physical demand (P=.004), temporal demand (P=.017), and effort (P=.006). External instrument clashing was significantly reduced in MAGS LESS suturing (P.001). The total operative time of MAGS LESS suturing was comparable to that of conventional LESS (P=.89).MAGS camera technology significantly decreased surgeon workload and improved ergonomics. Nevertheless, LESS suturing and knot tying remains a challenging task that requires training, regardless of which camera is used.

To provide an overview of the current research on renal tissue ablation, highlighting novel ablation techniques and technologies.As long-term data on renal radio frequency ablation (RFA) and cryoablation confirming their oncologic efficacy emerge, ongoing research aims at improving the treatment profiles of these techniques as well as developing novel methods for renal tissue ablation.Although nephron-sparing surgery is the gold standard treatment for small renal masses confirmed malignant, ablative therapies are an option in elderly patients, who may be poor surgical candidates. RFA and cryoablation have each been used for renal tissue ablation for over a decade but their efficacy in ablation of central lesions or lesions more than 3 cm in size is limited. Increasing ablation size and improving efficiency of thermal energy delivery are the goals of research in RFA and cryoablation. Novel ablation technologies including microwave ablation, irreversible electroporation and high-intensity focused ultrasound among others have undergone preliminary preclinical and clinical evaluation in select series but require further development and assessment of outcomes prior to routine clinical use for renal tumor ablation.

Complete stone removal is important in upper tract stone surgery. Unfortunately, even with the latest technologic advances, current methods only achieve 50% to 80% complete clearance of upper tract stones at the time of primary treatment. Our group has explored the novel use of peptide-coated iron oxide superparamagnetic microparticles that bind to calcium stones, allowing for extraction of these stones with magnetic tools. We present analytic and numeric models that characterize stone attraction performance for feasible magnetic tool sizes and stone magnetization levels.Magnetostatics equations are applied to a simplified, one-dimensional scenario of a spherical target coated with a variable amount of superparamagnetic particles, placed under the influence of a magnetic field aimed at vertical attraction (capture) of the target. Equations are parameterized in terms of (a) target size, ranging from 0.5 mm to 3 mm to represent stone sizes of interest, (b) effective magnetization per surface area delivered by the particle binding chemistry, and (c) distance to the field source.Target capture is predicted to be effective in the low, single-digit millimeter distance range, favoring smaller stones and then up to a practical upper limit of 3 mm diameter. Higher iron loading chemistries have a direct improvement in magnetic force and therefore increase the viability of the technique, albeit along an asymptotic trendline.We are able to characterize the potential for kidney stone capture via magnetic attraction. Computer-developed models show good correlation with experimental results using actual magnetized stone samples. Future research efforts can use the proposed techniques to estimate the performance impact of advanced magnetic tools and surface chemistries.

Conventional laparoscopic dismembered pyeloplasty (LP) is an established alternative to open pyeloplasty given equivalent intermediate-term outcomes and decreased morbidity. Laparoendoscopic single-site (LESS) pyeloplasty has the potential to further decrease the morbidity of LP, while yielding superior cosmesis. It is, however, technically very challenging even with the use of an accessory port, largely because of the difficulty of intracorporeal suturing through a single umbilical incision. Application of the da Vinci robotic surgical platform to LESS pyeloplasty (R-LESS) has the potential to overcome these limitations. We describe our technique for R-LESS pyeloplasty using the da Vinci Si robot. We have found that use of the robotic system in conjunction with certain technique modifications helps to reduce the technical difficulty of LESS pyeloplasty and to shorten the physical learning curve associated with the procedure.

This report suggests that laparoscopic single-site pyeloplasty of uteropelvic junction obstruction associated with horseshoe kidney is feasible, safe, and effective in select patients., Background and Objective: Pyeloplasty in horseshoe kidneys can be challenging due to aberrant vasculature, renal malrotation, and ectopic location. Fewer than 20 cases of minimally invasive (MIS) pyeloplasty in horseshoe kidneys have been reported in the literature to date. We herein report the first 2 cases of laparoendoscopic single-site (LESS) pyeloplasty for UPJ obstruction in horseshoe kidneys. Methods: Two patients with symptomatic ureteropelvic junction obstruction in horseshoe kidneys were treated with an Anderson-Hynes LESS pyeloplasty. This was performed using three 5-mm trocars through a single umbilical incision, plus an accessory 3-mm port at the anterior axillary line to facilitate suturing and subsequent drain placement. Results: Both patients had BMI

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Studies in other surgical populations have found that scarring is a relatively unimportant preoperative patient consideration when compared with surgical cure and safety, but that younger age was a significant factor influencing preference for ‘scarless’ surgery. The present study corroborates the findings of previous series, among patients who were contemplating kidney surgery. OBJECTIVE • To evaluate patient attitudes towards cosmesis relative to other considerations, before and after undergoing laparoendoscopic single-site surgery (LESS) vs laparoscopic/robot-assisted vs open kidney surgery. METHODS • Participants were provided with a survey querying demographic information, surgical history and importance of scarring relative to other surgical outcomes and considerations. • The relative importance of each outcome was recorded on a nine-level ranking scale, ranging from 1 (most important) to 9 (least important). • The median scores for each outcome were compared before and after surgery using the Wilcoxon signed-rank test, and by surgical approach using the Kruskal–Wallis test. • The importance of scarring was further analysed according to age (≤50 vs >50 years), surgical indication (oncological vs non-oncological), gender, and proportion of patients who had undergone previous abdominal surgery. RESULTS • A total of 90 patients completed surveys before surgery, of whom 65 (72.2%) also completed surveys after surgery. • ‘Surgeon reputation’ and ‘no complications’ were the most important considerations before surgery (median scores 2 and 3, respectively) and after surgery (median scores of 2 for both). • ‘Size/number of scars’ was the least important consideration before surgery (median score 8) and the second least important consideration after surgery (median score 7). • The median score for ‘size/number of scars’ was significantly higher for the LESS cohort before surgery (laparoscopic/robot-assisted vs LESS vs open surgery: 8.5 vs 6 vs 9; P = 0.003), but was nonsignificant after surgery (laparoscopic/robotic vs LESS vs open surgery: 7 vs 6.5 vs 7.5; P = 0.83). • The median score for ‘size/number of scars’ before surgery was significantly higher for younger patients (P = 0.05) and those with non-oncological surgical indications (P

Objectives To evaluate the efficacy of a self-retaining barbed suture (SRBS) in achieving a secure and haemostatic renorrhaphy during laparoscopic partial nephrectomy (LPN). To compare perioperative outcomes for LPN with SRBS with those for LPN with conventional polyglactin suture, with specific attention to warm ischaemia time, blood loss and need for postoperative bleeding interventions. Patients and methods Patients who underwent LPN between June 2007 and October 2010 were identified through an Institutional Review Board approved registry of oncological patients. Before July 2009, parenchymal repair after tumour excision was performed using absorbable polyglactin suture (Group 1), and subsequently, using SRBS (Group 2). Demographic, clinical, intraoperative and postoperative outcomes were compared for each group. Results LPN was performed in 49 patients in Group 1 and 29 in Group 2. Baseline demographic and clinical features, estimated blood loss, and transfusion and embolization rates were statistically similar for the cohorts. Mean warm ischaemia time (±SD) was significantly shorter for the SRBS group (26.4 ± 8.3 vs 32.8 ± 7.9; P= 0.0013). Bleeding requiring intervention (open conversion or transfusion ± embolization) was more common for Group 1 (9/49, 18.4% vs 1/29, 3.4%; P= 0.06). Conclusions The use of SRBS for parenchymal repair during LPN in humans is safe and is associated with a significant reduction in warm ischaemia time. SRBS use during LPN may also reduce rates of clinically significant bleeding. Prospective, larger studies to confirm the value of SRBS use in minimally invasive partial nephrectomy are warranted.

In pre-clinical studies, acute erythropoietin (EPO) administration has been shown to mitigate the deleterious effects of ischemia/reperfusion injury. We reviewed our clinical experience with intraoperative EPO administration as a potential renoprotective agent during laparoscopic partial nephrectomy (LPN). Patients who underwent LPN at our institution between August 2008 and March 2010 received 500 IU/kg EPO 30 min prior to hilar occlusion. Those who underwent LPN between August 2006 and July 2008 without receiving EPO were selected as controls. Demographic, clinical, perioperative, and estimated glomerular filtration rate (eGFR) data were compared for the cohorts preoperatively, and during short-term (

Surgical skills increasingly are taught in training laboratories outside the operating room. This change in paradigm has driven the development of surrogate training models for a wide range of surgical procedures. In urology, a growing number of procedures using minimally invasive techniques are performed. Consequently, the development of simulators for training and assessment represents a growing need. In this article, we review the currently available ureteroscopic simulators, including a critical assessment of relevant validation studies for each.

Purpose Ischemia/reperfusion (I/R) during partial nephrectomy (PN) contributes to acute kidney injury (AKI), which is inaccurately assessed using existent clinical markers of renal function. We evaluated I/R-related changes in expression in hypoxia inducible factor 1α (HIF-1α) and toll-like receptor 4 (TLR4), within kidney tissue and peripheral blood leukocytes (PBL) in a porcine model of PN. Materials and Methods Three adult pigs each underwent unilateral renal hilar cross clamping for 180 min followed by a 15 min reperfusion. The contralateral kidney served as control. Biopsies of clamped kidneys were obtained at baseline (time 0), every 60 min during the hypoxic phase, and post-reperfusion. Control kidneys were biopsied once at 180 min. Peripheral blood was sampled at time 0, every 30 min during the hypoxic phase, and post-reperfusion. HIF-1α and TLR4 expression in kidney tissue and PBL were analyzed by Western blotting. I/R-related histological changes were assessed. Results Expression of HIF-1α in clamped kidneys and PBL was below detection level at baseline, rising to detectable levels after 60 min of hypoxia, and continuing to rise throughout the hypoxic and reperfusion phases. Expression of TLR-4 in clamped kidneys followed a similar trend with initial detection after 30–60 min of hypoxia. Control kidneys exhibited no change in HIF-1α or TLR-4 expression. I/R-related histologic changes were minimal, primarily mild tubular dilatation. Conclusions In a porcine model of PN, HIF-1α and TLR4 exhibited robust, I/R-related increases in expression in kidney tissue and PBL. Further studies investigating these molecules as potential markers of AKI are warranted.

INTRODUCTION AND OBJECTIVES: The increased use of fluoroscopy exposes practicing urologists to frequent radiation exposure. The human eye is a highly radiosensitive part of the body and long-term exposure to radiation can initiate cataract formation. Many physicians now wear lead lined glasses for safety. We explored the radiation exposure of urologists at our institution to determine whether they are at an increased risk for cataract formation. METHODS: A retrospective review of a multi-surgeon, prospectively maintained database of fluoroscopic cases between 10/ 2013 to 10/2014 identified a total of 691 cases. The screening time, kV and mA were recorded from all cases in the operating room. The procedures were performed by different subspecialties of urology and included stent insertion, ureteroscopic lithotripsy, and percutaneous nephrolithotomy. We calculated the radiation dosimetry of urologists through the methods described by the National Council on Radiation Protection (NCRP) and extrapolated the dose exposure to determine risk of cataract formation. For the calculated dosimetry, technical specifications of the GE OEC 990 mobile C-arm unit were used. The surgeon was assumed to be standing at a distance of 75 cm with a scattering angle of 45 degrees to estimate the radiation dose to the surgeon’s eye. RESULTS: The average fluoroscopic time was 35.35 seconds per case. The average tube potential and tube current was 89.69 kV and 1.96 mA, respectively. Pediatric urologists used the least amount of fluoroscopic time, 11.86 seconds per case (p 1⁄4 0.0047). Endourology fellowship trained urologists utilized the longest time of fluoroscopy, 70.33 seconds per case (p < 0.0001), while non-endourologists utilized 27.24 seconds per case (p < 0.0001). This may be related to the complexity of the cases. The tube potential and current for endourology cases were recorded as 91.34 kV and 1.81 mA (p1⁄40.11). The total number of endourology cases over the past year was 131. Using this data, we then calculated the estimated radiation dose to the eyes for the most highly exposed urologists at our institution to be 5.64 mGy per case. For the past year, the total estimated cumulative dose would then be 738.84 mGy. CONCLUSIONS: Yearly eye exposure limits are currently defined at 150 mSv by the NCRP. Over the past year, our highest exposed urologists compiled an estimated dose of 0.5% of the annual limit. We conclude that fluoroscopy is a safe method in the urological field. With the use of newer radiation technologies and sensible radiation principles, the risk to the surgeon is diminishing.

Purpose: We evaluated the long-term results of laparoscopic hemicystectomy and bladder replacement with small intestinal submucosa (SIS) with ureteral reimplantation into the SIS material. Materials and Methods: A total of 12 minipigs underwent laparoscopic hemicystectomy. Six pigs underwent bladder reconstruction with SIS and ipsilateral ureteral reimplantation. The remaining 6 control pigs underwent hemicystectomy and primary bladder closure with ipsilateral nephroureterectomy. Preoperative and followup evaluations included blood chemistry, radiography and urodynamic evaluations. The 6, 3, 6 and 9-week, and 12-month followup evaluations included biopsies. At 1 year the animals were sacrificed. Histopathological and contractility studies, and reverse transcriptase-polymerase chain reaction for growth factors and basement membrane components were performed. Results: Bladder capacity and bladder compliance were similar in the 2 groups at all time points. One pig per group died, that is a control at the 9-month evaluation due to an anesthetic complication and an SIS pig 7 months after bladder reconstruction due to spontaneous bladder rupture at the anastomotic site. In the SIS group 4 of 5 surviving pigs had unobstructed reimplanted ureters without evidence of hydroureteronephrosis, while 1 had high grade obstruction at the reimplantation site. Histopathology study after 1 year revealed muscle at the graft periphery and center but it consisted of small fused bundles with significant fibrosis. Nerves were present at the graft periphery and center but they were decreased in number. Conclusions: Laparoscopic SIS bladder reconstruction and ureteral reimplantation into the SIS after hemicystectomy are technically feasible. However, compared to primary bladder closure no advantage in bladder capacity or compliance was documented.

We prospectively compared the systemic immune and stress response of patients who underwent laparoscopic total nephrectomy (LRN) (14) and open nephrectomy (ON) (10) for renal cell carcinoma. The ON group comprised open radical (4), open total (2) and open partial (4) nephrectomy cases.Only patients with no history of cancer or autoimmune disease and American Society of Anesthesiologists score 2 or less who were not using immunosuppressive drugs were selected. Peripheral venous blood was collected preoperatively and intraoperatively, and 24 hours, 2 weeks, 4 weeks and 3 months postoperatively. Blood was analyzed for stress markers (adrenalin, noradrenalin and cortisol), inflammatory response markers (C-reactive protein, white blood count and leukocyte count), lymphocytic response markers (CD3, CD4 and CD8), cytokines interleukin-2 and 4, interferon-alpha and tumor necrosis factor-alpha), HLA-DR expression and the proliferative response to mitogen stimulation using concanavalin A, phytohemagglutinin 10, and pokeweed mitogen.Mean tumor size +/- SD for ON and LRN was 5.6 +/- 2.4 and 4.5 +/- 1.6 cm, respectively (p = 0.21). The trends with time for all measured postoperative parameters were similar in the 2 groups. Inflammatory and stress response markers were statistically similar for in the groups at all time points. A significant difference between the groups was noted for the percentage of CD4+ and CD8+ lymphocytes. However, this difference was present preoperatively and there was no significant absolute change in these 2 parameters. The cytokine response and HLA-DR expression were similar in the 2 groups at all time points. Likewise, the lymphocytic stimulation index for concanavalin A, phytohemagglutinin and pokeweed mitogen were statistically similar for LRN and ON at all time points.The immunological and stress response after LRN and ON for renal cell carcinoma is similar. The few differences observed in measured parameters likely reflect preoperative differences in baseline and/or the contributory effect of anesthesia.

We assessed the usefulness of the LigaSure (Valleylab, Boulder, Colorado) vessel sealing system for vascular control during laparoscopic surgery and compared it with other available hemostatic modalities.A total of 31 domestic pigs were divided into 5 groups. In groups 1 and 2 the vessel sealing system was compared with titanium clips and Endo-GIA (United States Surgical, Stamford, Connecticut) staples. In group 3 the vessel sealing system was compared with standard Klepinger (Karl Storz, Culver City, California) bipolar forceps. In group 4 the harmonic scalpel and Trimax (United States Surgical) bipolar forceps were compared. In group 5 in vivo laparoscopic application of the vessel sealing system was evaluated.The 5 mm. laparoscopic vessel sealing system sealed arteries up to 6 mm. and veins up to 12 mm. in diameter at supraphysiological bursting pressure. We evaluated 13 arteries with a diameter of 6 mm. or less at a mean bursting pressure of 662 mm. Hg (range 363 to 1,985) and 11 veins with a diameter of 12 mm. or less with a mean bursting pressure of 233 mm. Hg (range 63 to 440). Collateral tissue damage extended 1 to 3 mm. from the application site. Standard bipolar energy with Klepinger and Trimax forceps was less reliable and in some cases vessel sealing could not be accurately assessed before vessel division. Collateral tissue injury was 1 to 6 mm. The harmonic scalpel did not reliably seal vessels larger than 3 mm. but resulted in the least acute collateral tissue injury of 0 to 1 mm.In the porcine model the LigaSure system is a viable option for laparoscopic management of arteries up to 6 mm. and veins up to 12 mm. in diameter.

We evaluated the safety and efficacy of laparoscopic partial nephrectomy with an arcing-gap electrosurgical snare in a porcine model.A novel electrosurgical snare, optimizing high current density arcing and parenchymal compression, was utilized for laparoscopic renal transection. Five farm pigs underwent unilateral laparoscopic polar partial nephrectomy; 6 weeks later, these same animals underwent contralateral partial nephrectomy just prior to sacrifice. Five additional animals underwent chronic (6-week follow-up) and acute open partial nephrectomies by the conventional surgical technique.The average time for transection with the snare was 5.6 minutes. In 9 of 10 cases, the snare provided satisfactory hemostasis. In the remaining case, additional argon-beam coagulation (ABC) controlled the minimal bleeding present after transection. In all 10 animals, the collecting system was transected. In six cases, application of the snare alone sealed the collecting system. No urinomas developed in the five animals followed for 6 weeks. At 6 weeks, the mean depth of injury at the center of the cut surface was 5.1 mm in the laparoscopic group and 3.9 mm in the open group.Laparoscopic partial nephrectomy with the arcing-gap electrosurgical snare is feasible in a porcine model. Application of the snare provides excellent hemostasis without the need to control the renal vasculature.

We evaluated the use of a poly-L-lactide-co-glycolide (PLGA) bioabsorbable ureteral stent after Acucise balloon incision (Applied Medical Resources, Rancho Santa Magarita, California) endopyelotomy in a porcine model.After unilateral Acucise endopyelotomy in 9 female Yucatan minipigs a self-reinforced PLGA stent was placed in 5 (group 1) and a 7Fr double pigtail Percuflex stent (Boston Scientific, Natick, Massachusetts) was placed in 4 (group 2). Preoperatively, and 6 and 12 weeks postoperatively plain x-ray of the kidneys, ureters and bladder, cystography, side specific creatinine clearance and retrograde ureterography were done. The contralateral ureters served as untreated controls. The 7Fr stents were removed at 6 weeks. All animals were sacrificed at 12 weeks after bilateral flow studies. Histological specimens from 4 sites along the urinary tract were graded on a healing score of 0-normal, to 3-severe changes.Side specific creatinine clearance was similar to preoperative values at 6 and 12 weeks. At the 2 time points plain x-ray of the kidneys, ureters and bladder in group 1 showed retroperitoneal stent fragments in 3 of the 5 animals, which was confirmed at autopsy. Retrograde ureterography in group 1 showed mild hydronephrosis in all 5 ureters and saccular diverticula in 4, which was similar in 2 and 3 animals, respectively, in group 2. Cystography demonstrated grades 1 to 2 reflux in 2 animals at 6 weeks but none at 12 weeks in group 1 and no reflux at either time point in group 2. Flow rates and healing scores were statistically similar in the 2 groups but the latter trended toward less favorable healing of ureteral musculature with application of the absorbable stent.In this pilot study the use of self-reinforced PLGA biodegradable ureteral stents was feasible after Acucise endopyelotomy in a porcine model with radiographic and fluid flow results that were relatively similar to those of standard 7Fr stents but with less favorable biocompatibility.

A secure and hemostatic renorrhaphy is the primary challenge of minimally invasive nephron-sparing surgery (MINSS). The laparoscopic surgeon's ability to maintain constant tension on the suture while oversewing the transected parenchyma and collecting system is difficult, even when using robotic technology. A self-retaining barbed suture (SRBS) is a recent innovation that maintains tissue apposition and tension using a novel “self-cinching” mechanism. We describe our technique for SRBS use during MINSS. In our experience, the use of SRBS in this setting is safe and improves suturing efficiency during the time constraint of warm ischemia. We believe that intracorporeal suturing with SRBS during MINSS may help shorten the learning curve associated with this technically challenging step and have adopted it in our standard practice.

Quantitative spectroscopy has been scientifically investigated since the 1800s, but application of spectroscopic techniques in medical diagnosis is relatively recent. Light reflectance and autofluorescence spectroscopy in the kidney and prostate have undergone extensive preclinical evaluation over the past decade. Initial promising findings with regard to differentiation of malignant from benign tissues and in characterization of tissue response to ischemia among others have been reported in select preclinical studies. However, limitations of current spectroscopic equipment, in spectral data processing, and a dearth of in vivo studies of these techniques in appropriate experimental models have resulted in their restricted use to the experimental setting, pending further development and clinical evaluation.

This study was conducted to evaluate the capability of detecting prostate cancer (PCa) using auto-fluorescence lifetime spectroscopy (AFLS) and light reflectance spectroscopy (LRS). AFLS used excitation at 447 nm with four emission wavelengths (532, 562, 632, and 684 nm), where their lifetimes and weights were analyzed using a double exponent model. LRS was measured between 500 and 840 nm and analyzed by a quantitative model to determine hemoglobin concentrations and light scattering. Both AFLS and LRS were taken on n = 724 distinct locations from both prostate capsular (nc = 185) and parenchymal (np = 539) tissues, including PCa tissue, benign peripheral zone tissue and benign prostatic hyperplasia (BPH), of fresh ex vivo radical prostatectomy specimens from 37 patients with high volume, intermediate-to-high-grade PCa (Gleason score, GS ≥7). AFLS and LRS parameters from parenchymal tissues were analyzed for statistical testing and classification. A feature selection algorithm based on multinomial logistic regression was implemented to identify critical parameters in order to classify high-grade PCa tissue. The regression model was in turn used to classify PCa tissue at the individual aggressive level of GS = 7,8,9. Receiver operating characteristic curves were generated and used to determine classification accuracy for each tissue type. We show that our dual-modal technique resulted in accuracies of 87.9%, 90.1%, and 85.1% for PCa classification at GS = 7, 8, 9 within parenchymal tissues, and up to 91.1%, 91.9%, and 94.3% if capsular tissues were included for detection. Possible biochemical and physiological mechanisms causing signal differences in AFLS and LRS between PCa and benign tissues were also discussed.

Purpose: The pattern of flow in the stented ureter (intraluminal and/or extra luminal) has only been defined for the standard pigtail stent. No data are available on stent flow for any specialty stents. To our knowledge we present the first investigation characterizing the type of flow through a stent (Poiseuille versus nonPoiseuille flow).Materials and Methods: Flow was measured in an unstented ureter, a standard 7Fr double pigtail stent and the 7/3Fr Tail † stent, 7Fr Spirastent ‡ and 14/7Fr endopyelotomy stent using a previously developed stent flow model. In vitro pressure flow studies were also done in nonfenestrated 14/7Fr, Tail and standard 7Fr stents. These stents were infused at a constant flow rate of 2 to 10 ml. per minute with monitoring of the corresponding pressure gradients. Resistance to flow was determined for these stents using pressure flow plots and Poiseuille’s law.Results: In vivo the 7Fr pigtail, 14/7Fr endopyelotomy and 7/3Fr Tail stents had statistically similar flow rates. Flow t...

Objectives. Ureteral stents all share one general goal, drainage, and one major drawback, irritative symptoms in the kidney and bladder. In an effort to preserve drainage while minimizing irritation, a lightweight, self-expanding mesh stent was designed. Herein, we compare the in vivo tissue reaction and flow characteristics of the mesh stent to a standard 7F double-pigtail polyurethane stent. Methods. Eight female Yucatan minipigs had bilateral stents placed: a mesh stent on one side and a standard 7F stent on the opposite side. Imaging and flow measurements were obtained in 4 pigs at 1 week and in another 4 pigs at 6 weeks. Following this procedure, the stents were removed, and the kidneys, ureters, and bladder were harvested en bloc for a blinded histopathologic analysis. Results. The degree of stent-related tissue reactivity was low for both stents and appeared similar for the ureter and bladder. Overall, the mesh stent resulted in a decrease in inflammation along the urinary tract at 1 week, but this result was statistically insignificant ( P = 0.55). Flow rate through the mesh stent tended to be greater than for the polyurethane stent both at 1 week and at 6 weeks. Conclusions. Overall, the mesh stent appeared to be well tolerated and provided for excellent flow.

Objectives. Morcellation with the Cook high-speed electrical laparoscopic (HSEL) morcellator in an impermeable nylon/plastic sack (LapSac) has remained unchanged since its inception nearly one decade ago. Sack deployment and specimen entrapment remain relatively difficult, and morcellation with this device is expensive and relatively slow. As such, in an effort to facilitate specimen entrapment and morcellation, we adapted two currently available electrical morcellators (the Steiner gynecologic morcellator and the electrical prostate morcellator [EPM]) for renal morcellation and compared them with the HSEL morcellator. Methods. All morcellation was performed through a simulated abdominal wall under direct laparoscopic vision. Ten porcine kidneys were ablated with each of the following techniques: HSEL morcellation in a LapSac; HSEL morcellation in a fluid-filled LapSac; Steiner morcellation in an insufflated Endocatch sack; and EPM morcellation in a fluid-filled Endocatch sack. A modified laparoscopic trocar was constructed and used for the Steiner and EPM morcellation. The time to complete morcellation, morcellation product size, and entrapment sack integrity were evaluated for each technique. Cost data for each morcellator are also presented. Results. The mean morcellation time for the Steiner, HSEL dry, HSEL wet, and EPM morcellation was 6.0, 15.9, 14.7, and 26.0 minutes, respectively. The mean fragment size for these morcellators was 2.97, 0.65, 0.62, and 0.013 g, respectively. A single entrapment sack perforation was documented in a LapSac during routine HSEL morcellation. Conclusions. Renal morcellation with all three morcellators is feasible. The Steiner morcellator combined with an Endocatch resulted in more rapid morcellation and larger morcellation products.

Purpose: Flexible ureteroscopes smaller than 9Fr are widely used in endourology. We systematically evaluated the functional durability of these instruments in the clinical setting.Materials and Methods: We performed ureteronephroscopy 92 consecutive times in 84 patients at our hospital using a flexible Storz model 11274AA, ‡ ‡Karl Storz Endoscopy, Tuttlingen, Germany. Circon-ACMI model AUR-7, § §Circon Corp., Santa Barbara, California. Wolf model 7325.172 ∥ ∥Richard Wolf GmbH, Knittlingen, Germany. and Olympus model URF/P3 ureteroscope ¶ ¶Olympus Optical Co., Melville, New York.. Preoperatively and postoperatively we evaluated all flexible ureteroscopes for luminosity, irrigant flow at 100 mm. Hg, number of broken image fibers and active deflection range. During the procedure a record was kept of the duration that the endoscope remained in the urinary tract, average irrigation pressure, method of insertion, various devices used within the working channel, need for lower pole access, and surgeon overall im...

A variety of biodegradable organic materials have been used for bladder wall replacement. In some instances, partial replacement has been done using laparoscopic reconstructive techniques. However, to date, this activity has been limited to small patches. Herein, we present the initial experience with laparoscopic sagittal hemicystectomy and the use of laparoscopic reconstructive techniques to replace half of the bladder with small-intestinal submucosa (SIS) and to reimplant the ureter into SIS.Six female minipigs (20-25 kg) underwent transperitoneal laparoscopic sagittal hemicystectomy; the excised bladder wall was replaced with a 5 x 15-cm patch of SIS (Cook Biotechnology, Spencer, IN). The ipsilateral ureter was reimplanted through a small incision in the graft and secured with two sutures. Cystoscopy and cystometrograms were performed under general anesthesia preoperatively and at 6 and 12 weeks postoperatively. Tissues were harvested at 12 weeks.The procedure was successful in six animals (left three, right three). During cystoscopy at 12 weeks, the area of the graft was not distinguishable from normal mucosa. Cystometrograms revealed maintenance of volume and compliance, with volumes of 338, 343, and 369 mL and intravesical leak-point pressures of 37, 59, and 39 cm H2O at 0, 6, and 12 weeks, respectively. Antegrade ureterograms demonstrated extrinsic obstruction, minimal (two), moderate (three), or complete (one), at the ureterovesical junction. The kidney associated with the completely obstructed ureter was grossly hydronephrotic at sacrifice. Histologically, patchy epithelialization of the graft with a mixture of squamoid and mature transitional-cell epithelium was found.Laparoscopic hemicystectomy with replacement of the bladder wall and implantation of the ureter into the SIS graft is a feasible procedure. Clinical application awaits improvements in the method of ureteral reimplantation and longer follow-up to assess for ingrowth of muscle and nerve fibers.